Spark gap



JuKly 5, 1927.

H. H. osBoRN SPARK GAP Filed June l0. 1921 2 Sheets-Sheet 1 \\/////////////2 rI////////////////l//////'///f yJill!! 5 1927" H. H. osBoRN SPARK GAP Filed June l0. 1921 2 sheets-sheet 2 Patented July 5, 1927.

UNITED STAT-Es ra*rlfzn'ronirica.

HOWARD H. OSBORN, OF CHICAGO, ILLNOS, ASSIGNR TO H. G. FSCI-IER &COMPANY,

or CHICAGO, ILLINors, n ccitrcnnrioiv or iLLiNors.

SPARK GAP.

'Application tiled June 10, 1921. Serial No. 476,640.

This invention relates in general to apparatus for generating elect-ric current of high frequency and voltage, and has more particular reference to spark gaps employed in such apparatus, the particular embodiment et the invention to be hereafter described being or' that character comprising a part ot the electro-therapeutic equipment employed by physicians. Y

A principal object of the invention is the provision of a simplied and highly efiicient sparkv gap dispensing with certain elements of construction heretofore deemed essentiai, and being susceptible oi' comparatively inexpensive commercial production.

My invention also contemplates the provision in a device ot the character described of parts particularly adapted for the pur-- poses heretofore stated and at the same time serving to mufHe vthe sound and to dim or modify the light resultant from the sparks' at the gaps.

A still further object ot the invention is the provision of a sparking device having the above characteristics in combination with means for Ventilating the cells formed .by the multiple gaps, and with meansfor varying the length of the spark by rendering inoperative one or more individual gaps.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the 'following description, Which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

Referring to the drawings:

Figure 1 is a plan view of a multiple spark gap embodying the principles of my invention Fig. 2 is a longitudinal vertical section through the same;

Fig. 3 is a section taken transversely of the device;

Fig. 4 is a perspeetivevof one of the conductive disks;

Fig. 5 is an enlarged view of the bushing through which the short circuiting rod eX- tends; and

Fig. 6 is a perspective of the short circuiting rod.

The embodiment of my invention, shown by way of illustration in the drawings, comprises primarily a pair of end holding plates 11, three glass connecting rods, 12, 13, eX-

tending therebetween, and a seriesl of sparking cells indicatet generally by the reference cl acter 11i. Upon theend vplates 11 are alf'propriate sockets 15 for the glass con-v nectors '12. In the upper,y parts of these plates are slots 16 for the reception of screw threaded proiections 17 o sockets 18 1n which he third glassconnector 13 is retained. The material about `the lowerpart of the slots 16 is beveled, and nuts 19 having minted er beveled noses 21 are provided and `=nted tobe screwed upon the 'projections At opposite endsot the seriesof sparking cells are disks 22against which end clamps 23` pressed by means of screw posts 24; rling through the plates ,11, and by is of which the entire series of sparking enten l, rEhe screw posts 2e, in the present instance, constitute also binding posts with which the wires ot the circuit may be connected to include the sparking device therein. The sparking cells `are formed by the disks 22 and similar disksr25 arranged in .series through the device.r rlhe disks 22 are provided with studs 26 secured thereto by means ot screws 27 and extending inwardly. Each disk 25 is equipped with oppositely extending studs or units 28 and 29 which are secured together by means of screws 31 extending through apertures 32 in the central portions of the disks, the gaps 33 being provided between the opposed studs or units 26, 28 and 29. The electric current is passed through the binding posts'2l1, the disks 22 and 25. these being formed of conductive material, and through the studs or units 26,

28 and 29, the sparks occurring at the form and composed of glass which is eX` teriorly ground in order to dim or modify the light from the sparks. It will be seen that each of these members encloses one sparking gap and that the cells are formed merely by the use of t-he conductive disks and single housings. At the same time accidental short circuiting is prevented, and accurate occurrence of sparking insured by the use of appropriate insulating material. 1n said housings or encasing members.

Extending through the binding posts 24 and the end clamps 23 is a passageway 85 through which compressed air from a tube 36 is 4introduced into the device, and the disks 22 and 25 are provided with apertures 37 preferably arranged in staggered relation to permit passage of air between the gaps 33 and through the various cells. The course of air is thus that indicated by the arrows, it being introduced through one binding post and out at the other.

The disks are recessed at points 38 whereby to engage the appropriate connectors 12, 13, and are of such dimension that they engage the other connector 12 at 39 sothat said disks are held firmly in place between the connectors. In order to vary the length of the spark the disks are provided with aligned apertures 41 through which a short circuiting rod 42 having an insulating handle 43 and a split end 44 is adapted to extend. A bushing 45 is provided upon one of the plates or disks 22, being adapted t0 be positioned thereon by means of a slot 46 appropriately formed to fit upon the edge of the disk. It will be apparent that by inserting this rod through a greater or less number of the disks, any desired number of them may be short circuited so that sparking will occur only between the units on the other disks. It will be apparent that with the foregoing construction I have provided a spark gap of comparatively few parts, simply arranged, and etlicient in operation.

It is though that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without 'departing from the spirit and scope of the invention or sacrificing all' of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

I claim:

1. An electric spark gap, comprising a series of cells, each composed of spaced disks of current conducting material provided with projections extending into vthe cell in opposed relationship and a ringvot opaque insulating material eccentrically position-ed and extending between said disks and enclosing said projections to insure sparking therebetween, means for clamping the disks and rings of the several cells together to form a unitary apparatus, and current conducting means associated with the disks at the opposite ends of the apparatus.

2. An electric spark gap, comprising a series of cells, each composed of spaced disks of current conducting material provided with projections extending into the cell in opposed relationship and a ground glass ring eccentrically positioned and extending between said disks and enclosing said projections to insure sparking therebetween, means for clamping the disks and rings of the several cells together to form a unitary apparatus, and current conducting means associated with the disks at the opposite ends of the apparatus.

HOWARD H. OSBORN. j 

